Code Health: Replace Anonymous Runnables

Replace Java anonymous classes implementing Single Abstract Method (SAM) interfaces with lambdas to leverage Lambda Grouping and reduce binary size.

Goal: Clean up all occurrences of this pattern in the codebase.

Relevant Resources & Style Guides

• Optimization Advice: optimization_advice.md
• Implementation Patterns: patterns.md
• Discovery Script: find_candidates.py
• Automated Review Protocol: automated_review.md

Workflow

[!IMPORTANT] Execution Protocol: Execute all steps sequentially one by one. Do not skip any step. Use rg (ripgrep) for searches.

Step 1: Workspace Preparation

Follow the workspace preparation steps in workspace_preparation.md to ensure a clean and updated environment.

Step 2: Discovery & Batch Selection

1. Follow the Discovery & Batch Selection workflow to run the scanner.
2. Verify SAM Candidates (Subagent Verification): If auditing a specific subsystem or directory, the raw scanner might return false positives (e.g. abstract classes or interfaces with multiple methods). To filter these out dynamically:
   • Spawn a self subagent.
   • Pass it the verification prompt template from subagent_verification.md along with the list of raw candidates.
   • Use the subagent's verified list as the final batch.
3. Present the verified candidates to the user and ask for explicit approval before proceeding.

Step 3: Refactoring & Implementation

Process the candidates by handling them one file at a time, and applying modifications inside each file one instance at a time. This ensures stability and allows for precise verification.

Refactoring Guidelines:

• Convert single-method anonymous classes to Java lambdas.
• Warning: Skip if the method has annotations (like @JavascriptInterface or @SuppressLint). Do not attempt to move @SuppressLint to the field or enclosing method to bypass this, as it may not suppress the warning on the lambda.
• Warning: Skip if the anonymous class body uses this to refer to itself.
• Warning: Skip if the anonymous class is in a field initializer and references blank final fields initialized in the constructor (causes compile error).
• Warning: Do not convert View.OnTouchListener to lambdas. These often trigger ClickableViewAccessibility lint warnings if they do not call View#performClick(), and converting them can break existing lint baselines.
• Refer to patterns.md for concrete examples.
• Ensure no functional changes are introduced.

Step 4: Validation

1. Code Formatting: Run git cl format to format changes.
2. Mandatory Final Review: Follow the Automated Review Protocol to delegate a final review of the patch. Proceed only after it returns PASS.

Step 5: Verification

Follow the Verification workflow.

Step 6: Submission

Invoke the Submission workflow. Pass the following context variables:

• Branch Name: cleanup-replace-anonymous-runnables-[component-name]
• Commit Hashtag: Code Health
• Cleanup Title: Replace anonymous classes with lambdas in [Component]
• Cleanup Description: "Convert Java anonymous classes implementing SAM (Single Abstract Method) interfaces to lambdas. This allows R8 to perform Lambda Grouping and merge them, reducing overall DEX/binary size."
• Parent Bug: 541671762
• Bug ID: "none"
• Omit Skill Attribution: "true"
• Cleaned Component: The parent directory of the batch.
• File Count: Number of files cleaned up.